Hoist



Sept. 29, 1925. 1,555,094

, T. E. ADAMS HOIST Filed June 2 1923 4vsheets sheet 1 Sept. 29, 1925.

T. E. ADAMS HOIST \Filed June 20. 25 4 Sheets-Sheet 2 Sept. 29, 1925.1,555,094

T. E. ADAMS HOIST Filed June 20, 1923 4 Sheets-Sheet S I ii km a 4aSept. 29, 1925. 1,555,094

'r. E. ADAMS HOIST Filed June 20, 1923 4 Sheets-Sheet 4 film M MMPatented Sept. 29,, 1925.1

UNITED v STATES THOMAS E. ADAMS, or CLEVELAND, 01110.

HOI-ST.

Application filed June 20, 1923. Serial No. 646,511.

To all whom it may concern. I Be it known that I, ,THoMAs E. ADAMS,

a citizen of the United States, residing at.

Cleveland, in the county of Cuyahoga and State of Ohio, have invented acertain new and useful Improvement in Hoists, of which the following isa full,-clear, and exact description, reference being had to theaccompanying drawings.

My invention relates to hoisting machinery, and in particular to aportable electric hoist,-. although certain of its features are of moregeneral application as will hereinafter appear. I

In fact, the fundamental thought which constitutes the essence of myinvention and.

the nucleus of the improvements and de-.

velopments herein disclosed; is that of provlding an. internal worm gearand a worm cooperating therewith the arms of wh1ch is in substantiallythe central plane of "the wheel; and the wide range of utility of anarrangement of this kind is self-evident. As to this basic thought, theobjects in view are to greatly increase the efficiency and holding powerof worm gearing; to render the same more compact; to improve thelubricating facilities of such gearing; and to provide an arrangementwhich adapts itself more readily to certain circumstances, and to agreater number of uses, than prior forms of worm gearing.

That the nature of my invention as it pertains to improvements inportable hoists may be better understood and its advantages more fullyappreciated, brief reference may be made to prevailing types of portablehoists by way of comparison. For example, one object of m invention iscompactness, and another is lightness, where as little has heretoforebeen accomplished in these direc tion s-in the designing of hoists ofthe class to which my invention particularly relates. Another object isto provide a hoist that will sustain any load within the range of itslifting capacity with absolute certainty without the aid of a brake. Inthe case of my improved hoist a brake is employed only for the purposeof obtaining accuracy in the stopping of a load in suspension. 1

Another object of my invention is to pro vide a unique gear arrangementcharacterized by two sets of worm gears in series which effects thehighly desirable gear reduction and increased power without theobjectionable number of gears usually employed in the attainment ofthese ends. This feature contributes to the compactness and lightness ofthe structure and is responsible for the positiveness with which thehoist sustains its load. As will be gathered from this, this geararrangement is especially suitable for the purpose at hand, although itsadaptability to other uses will be apparent.

Further objects of the invention are to provide a hoist of the aforesaidcharacter that is very powerful for one of its size and weight, and issubstantial and durable; to provide a portable hoist that may be readilyhandled by one man in that by engaging the liftingcable to a support inthe vicinity of the one from which it is desired to sus pend the hoist,the hoist may beoperated to cause it to climb the cable so that all theoperator need do after it has attained the desired elevation is toengage its suspension hook with the trolley or other support from whichthe hoist is to be hung; to provide for various cable and pulleyarrangements whereby the hoist may be caused to lift light loads quicklyand heavier loads more slowly with a proportional increase of power; toprovide an electric hoist that will safely hold its maximum loadwhenever the electric power ceases; to provide means for stopping thehoistautomatically when the load has reached a given elevation therebyto prevent damage should the operator through any cause fail to shut offthe power; and to provide an electric hoist wherein, by the use of asingle element or cable, the operator may start, stop or reverse themotor, or apply the brake for effecting an accurate stop.

The foregoing objects, with others hereinafter appearing, are attainedin the embodiments of the invention illustrated in the accompanyingdrawings wherein Fig. 1 is a sideelevation of my improved portableelectric hoist with a part of the casing broken away to reveal eertainstructural features; Fig. 2 is a perspective view of the control elementor cable; Fig. 3 shows, more or less diagrammatically, the manner ofelevating the hoist to position for use; Fig. 4 is a central verticalsection through the hoist at right angles to the plane of Fig. 1 and ona .scale considerably enlarged over that of Fig.

1; Fig. 5' is an enlarged sectional detail of the combined "worm andworm wheel and its mounting; Fig. 6 is a sectional detail,

substantially on the line'66 of Fig. 4,

' stator 3 is supported in a plane transverse theinclined axis of thecasing, and the edges of the casing sections come together about thestator. The primary winding 4 is suitablyengaged within slots or groovesof the stator, while the secondary winding, so-

called, is made up of conductor rods 5 which extend through thelaminations of the rotor 6 and are connected at their ends to the endrings 7 and 8. The latte'r ring 8 (Fig.

4) insteadof being flat, as usual,-1s cylindrical .so as to serve as abrake drum, as will presently appear. From this brief description of therotor it will be recognized as one of the well known squirrel-cage type.While on this point it may be explained that end ring 7 might also bemade cylindrical and have associated with it a magnetic brake which,according to common practice, is automatically set by a spring.

when the current to the motor is'shut oil, and maintained inindl'ec'tive condition as long as the current flows; it being rememberedthat in brakes of this character the windings of the brake mechanism andmotor are in series. Illustration of this is deemed unnecessary as itwould require only the changing of ring 7 to a form substantially likethat of ring'8 and the supplying of the well known magnetic brakemechanism.

The rotor is clamped between flanges 10 and 11 upon the motor .shaft 12,the flan 10 engaging an abutment 13 on the sha t, while a nut 14, thatisapplied to a threaded portion of the shaft, engages the flange 10.

The respective upper and lower ends of the shaft 12 are journaledwithin'suitable antifriction bearings 16 and 17 which are containedwithin cavities formed in the casing sections, the cavity whichhousesthe hearing 16 being closed-by a cap 18 containing a washer 19 ofsuitable packing material so that lubricant supplied to the bearing 16will not find its wayto the electrical elements of the motor.

A suitable distance below the stator, the casing is divided by apartition 25 having acentral aperture through which the lower end of themotor shaft extends, and the partition incorporates a housing 26 withinwhich an anti-friction bearing 27 is con tained which serves to supportthe motor shaft intermediate its ends. In a reduced annular portion ofthe housing 26 is contained a washer 28 of packing material whichprevents lubricant, present in the compartment below the partition 25,from passingfrom the under to the over side of the partition should -thehoist be inverted during handling. 7 P

A worth 30 is secured to the lower end of the motor shaft and mesheswith a worm gear 31 that is formed about the waist or. equator of what Ishall term a. combined worm and worm gear 32, the end portions whereofare provided with threads. This combined worm and worm gear isgineffect, a worm having the central portion of its thread interrupted, thelead of the threads at the two ends being one and the same, andtherefore, in efiect, continuous.

A hoisting drum 35, shown as provided with the usual cable groove,surrounds the motor casing and is supported therefrom through ballbearings 37 which operate between inner and outer races 38 and 39,respectively, the former being fitted to annular shoulders 40 of themotor casing, and the latter having their peripheral portions threadedand screwed into the internally threaded edge portions of the drum 35.Near their inner edges, and on their inner sides, the ball races 39 aregrooved to receive expanding spring rings 41 which constitute abutmentsfor the inner edges of the inner ball races. 7 Preferably the ball racesare stamped from sheet metal of suitable gauge and quality, such amethod of production insuring accuracy and uniformity,

as well as cheapness. Rings 42, of suitable packing material, areinterposed between the inner edge portions of the outer ball races andthe adjacent portions of the motor casing for the purpose ofexcludingdust from, and retaining lubricant within, the casing.

An internal worm gear 45 extends about the interior of the drum 35 andis preferably --formed integral therewith, and the teeth of said wormgear mesh with the threaded portions 32 of the combined worm and wormgear 31. The lower casing section 2 is provided with brackets 46 (Figs.

1 and 5) which overhang theworm gear 45 and support a? stub shaft 47whereon the combined worm and worm gear 31 is mounted through.anti-friction bearings 48. Suitable means,.such as a cotter pin 49,extending through registering holes in one of the brackets 46 and theshaft 47 and serves to retain the shaft against longitudinaldisplacement.

Frames 50 are disposed on opposite sides of the motor casing and aresecured thereto by bolts 51 and 52 which passthrough the casing andthrough portions of said frames. The frames are further secured to themotor casing by bolts 53 which assist in securing the sections 1 and 2of the motor casing together. To lugs 55 of the frames 50 are pivotallyconnected the ends of a yoke 56 which has swiveled to it the suspensionhook 57 by .means of which the hoist is hung from a suitable sustainingstructure. A loop 60 is Obviously, in lieu of the cable arrangement justdescribed, a second sheave block may be hung from the loop 60, and thecable 64 en gaged over it and the hook 63 suitably connected to thesheave block 67, thus decreasing the speed with which the load would belifted when the motor is running at a given speed, while proportionatelyincreasing the power. Or, a double sheave block could be substituted forthe sheave block 67 and a single sheave block suspended from the loop60, with an appropriate arrangement of the 'cable 64, which wouldfurther increase the lifting power of the hoist. Thus, by using multiplesheave blocks, the power may be in creased to whatever is desired. Theobviousness of these arrangements make specific illustrationunnecessary.

An expanding non-magnetic brake shoe 70 (Fig. 6) is located within theend ring 80 which, as previously stated, constitutes a brake drum. Tothe inner side of the central portion of the shoe is attached abifurcated fitting- 71 which embraces a stub 72 that is secured to andrises from the partition 25 (Fig. 4). A spring 73, which has its endsconnected, through fittings 74, with the ends o the brake shoe, tends tocontract the shoe and engage opposed abutments 75, shown as formedintegral with the fittings 74. with the. opposite sides of a cam 76 thatis mounted upon a stud 77. An arm 78, which is fixed with respect to thecam 76, has its free end pivotally connected to one end of a link 79,the other end of the link being simi larly connected at 80 to a lever 81that is pivoted at 82 to the motor casing. A spring 85 tends to maintainthe lever normally in close proximity with the casing. The free end" fthe lever 81 is shown as provided with; an eye 86 for the connection, asthrough a snap 87, of a brake control element or cable 88.

lVithin a hollow boss 90 that is formed in one side of the upper section1 of the motor casing are supported contact posts 91, which h veconnection, through the leads'92, with certain sections of the primarywinding 4,

in accordance with usual construction of three-phase induction motors.The posts 91 are preferably supportedupon and insulated from asubstantial stool 94, the legs 95 whereof extend out over the adjacentportion of the winding 4 and are secured to the stator 3. A plug 96 isdesigned to fit within the boss 90 and contains sockets 97 for thereception of the contact posts 91.

The plug 96 may be fitted into the boss 90 in either of two positionswhich are 90 apart. \Vhen the plug 96 occupies one of its two angularpositions within the boss 90, connections are established which willcause the motor to run in a given direction; but when the plug isinserted into the boss 90 in v its other position it will establishconnections causing the motor to run in a reverse direction. This willbe readily understood by those familiar with the type of motor inquestion, and the arrangement of contacts is a matter of electricalexpediency.

In Fig. 3 I have shown more or less diagrammatically a track 100 onwhich a trolley 101 is mounted. The trolley may be shifted to anyposition along the track, but at all times maintains electrical contact,through shoes or brushes shown conventionally at 102, with electricalconductors 103. A connection similar to that just decribed as comprised,generally, of the posts 91 and sockets 97 occurs at 104 on the trolley101. 105 indicates a cord or cable containing electric wires orconductors through which electrical connection is made between thetrolley and the motor.

This cord or cable terminates at one end in branches 106 and 107 (Fig.2) the former having connection with the block 96, and the latter with ablock 108 which constitutes a part of the previously mentionedconnection 104 of the trolley 101. The opposite end of the cord or cable105 has branches 110 and 111 which carry. respectively, a socket member112 and a plug member 113, of a separable switch. For convenience andthe avoidance of confusion when operating the hoist, the brake controlcord or cable 88 may be incorporated in the cord or cable 105.

When the hoist is suspended from the trolley 101 and is in readiness foruse, the plug 108 is inserted in the trolley connection 104 and the plug96 inserted in the boss 90 of the motor casing. Now, when it is desiredto lift a load, thelifting hook or grapple is engaged with the load andthe plug member 113 is inserted within the socket member 112 of theseparable switch with the indications 112 and 113 of the respectivemembers 112 and 113 opposite each other. Current will be directedthrough the motor to cause it torotate the drum in a direction to liftthe load. As soon as the switch members 112 and 113 are separated, theload will be stopped. To prevent moverse to that wherein the indications112 and 113 are in register.

To guard against damage which would occur should the operator throughcarelessness or other cause fail to open the switch when hoisting aload, I provide the following mechanism: 115 is a stub shaft jour, naledwithin a boss 116 that is formed on the motor casing, and to one end ofthe shaft is secured a lifter 117 while an arm 118 is fastened to theother end thereof. The free end of the arm 118 is so disposed to theedge of the drum 35 as to be engaged and depressed by the cable 64 whenthe latter arrives at the adjacent edge of the drum. The free end of thelifter 117 normally reposes beneath one end of an elongated head 120wherewith the plug 96 is equipped, the opposite end of said headextending over a rib 121 that is formed on the adjacent frame 50.Consequently, when the load has been elevated at distance determined bythe entrance of the cable 64 into the last convolution of the drum 35,the arm 118 will be depressed by the cable thereby to elevate the lifter117 and kick the plug 96 out of the boss 90 and open the circuit, thehead 120 of the plug rocking upon the rib 121 during the operation. Theload will then be held suspended, without danger of coasting due to theeffective locking of the worm gears, until the operator again insertsthe plug 96 within the boss 90. WVhen this is attempted, he isrestrained, by the elevated condition of the lifter 117, from placingthe plug in its former position and is compelled to insert it in itsother position which will result in reversing the motor and lowering theload.

A convenient method of elevating the hoist to its suspended position isillustrated in Fig. 3. The cable 64 may. be run oif the drum 35 andcarried up a ladder 125 and engaged about a support, such as a beam 126.The plug 108 is inserted in the trolley connection 104, while the switchmember 112, through a suitable adapter (not shown), may be engaged withthe boss 90 of the motor, thus placing the motor in circuit with theelectrical conductors 103 and causing it to operate in a direction towind up the cable on the drum and by so doing lift the hoist to thedesired elevation. The operator then engages the suspension hook 57 ofthe hoist with the elevis 127 of the trolley, or with any other supportfrom which he desires to hang the hoist. When this is done, he removesthe adapter carried by the switch member 112 from the boss 90 andinserts the plug 96, at the same time snapping the brake control cord orcable 88 to the lever 81.

In the manually operated hoist, illustrated in Figs. 8 and 9, the drumis designated 130, and it is supported, through a ball bearing 131, froma frame 132 made up of two side members between which the ballsupporting and retaining ring 131 is clamped. A shaft 133 is supportedby the which enclose the threaded ends of the worm I 134 and providelubricant'chambers. Packing rings 139 are interposed between theportions of the casings 137 which surround the openings through whichthe worm is engaged and adjacent smooth portions that are formed on theworm, thereby to prevent egress of the lubricant and ingress of dust orgrit. The two halves of the frame 132 are connected together by bolts140, the one occurring at the top of the frame mrving as a means forconnecting a yoke 141 to the frame, A suspension hook 142 is swiveled tothe yoke. connected a loop 143 through which a hook 144, connected toone end of the cable 145, is engaged. The other end of the cable isfastened to the drum, as indicated at 146. It is evident that thepresent modification To another of the bolts 140 is is susceptible tothe same sheave block and cable arrangements as were mentioned inconnection with the former embodiment.

Having thus described my invention, what I claim is':

1. In combination, a drum, an internal worm gear carried by the drum, aworm meshing with the worm gear, and means for driving the worm.

2. In combination, a drum, an internal worm gear carried by the drum, aworm meshing with the worm gear, and driving mechanism inside the drumand having operative connection with the worm.

3. In combination, a supporting structure, a drum rotatably supportedthereby, an internal worm' gear carried by the drum, a worm rotatablysustained by the structure in mesh with the worm gear, and means fordriving the worm. I

4. In combination, a supporting structure, a drum rotatably supportedthereby, an internal worm gear carried by the drum, 9.

worm rotatably sustained by the structure in mesh with the wormgear, anddriving mechanism carried by the structure and having operativeconnectionwith the worm.

5. In combination, a supporting structure, a drum rotatably supportedthereby, 3.1'1'111- ternal worm gear carried by the drum, a wormrotatabl sustained by the structure in mesh with t e worm gear, saidworm incorporating a circumferential, gear, and means for rotating thelatter gear.

6. In combination, a supporting structure, a drum rotatably supportedthereby, an in-' ternal worm gear carried by the drum, a worm rotatablysustained by the structure in mesh with the worm gear, said worm havinga Worm gear about its equator, and driving mechanism sustained by thestructure and incorporating a worm meshing with the equatorial wormgear.

7. In combination, a drum, a supporting structure having bearings spacedapart axially of the drum and through which said drum is rotatably suported by the structure, an internal worm gear extending about theinterior of the drum, a worm meshing with the worm gear, and means forrotating the worm.

8. In combination, a drum, a supporting structure having bearings spacedapart axially of the drum and by which said drum is rotatably supported,an internal worm gear extending about the interior of the drum, a wormsustained by the supporting structure in mesh with the worm gear,driving mechanism supported by said structure, and operative connectionsbetween said driving mechanism and the worm.

9. In combination, a drum, a supporting structure having bearings spacedapart axially of the drum and by which said drum is rotatably supported,an internal worm gear extending about the interior of the drum, a wormsupported by the structure in mesh with the worm gear, said worm incorporating a circumferential gear, driving mechanism carried by thestructure, and diving connections between said mechanism and saidcircumferential gear.

10. In combination, a drum, a supporting structure having bearingsspaced apart axially of the drum and by which said drum is rotatablysupported, an internal worm gear extending about the interior of thedrum, a worm rotatably supported by the structure in mesh with theinternal worm gear, said worm having a worm gear extending about itsequator, and driving mecha nism carried by the structure andincorporating a worm meshing with the equatorial worm gear.

11. Ina hoist of the class set forth, the

combination of a motor, a drum surrounding the motor and rotatablysupported thereby,

an internal worm gear extending about the interior of the drum, and aworm driven by the motor and meshing with the worm gear. 12. In a hoistof the class set forth, the combination of a motor involving a casing, adrum surrounding the motor casing','sai casing having bearing portionsin parallel planes spaced apart axially of the drum and whereon said'drum is rotatably supported, an internal worm gear surrounding theinterior of the drum, a worm supported by the casing in mesh with theinternal worm gear, said worm having a worm gear extending about itsequator, and a worm on the motor shaft meshing with .the equatorial wormear. c 13. In a hoist of the classset forth, the combination of a motorinvolving a casing, a drum surrounding the motor casing, said casinghaving bear ng portions in parallel planes spaced apart axially of thedrum and whereon said drum is rotatably supported, an internal worm gearsurrounding the interior of the drum, a worm supported by the casing inmesh with the internal wormgear, said worm having a worm gear extendingabout its equator, a worm on the motor shaft meshing with the equatorialworm gear, a brake drum carried by the rotating element of the motor, abrake member supported in operative relation thereto, and vmeans foractuating the brake member.

14:. In a hoist of the class set forth, the

combination of an electric motor of the induction type having aso-called squirrel cage rotor winding in which one'of the end rings isconstituted of a cylindrical member serving as a brake drum, the motorinvolving a casing, a drum surrounding the motor casing, the casinghaving bearing portions in' a parallel planes spaced apart axially ofthe drum and through which the drum is rotatably supported, an internalworm gear extending about the interior of the drum, a worm rotatablysupported by and within the motor casing in mesh with the internal wormgear, said worm incorporating a'circumferential gear, and drivingconnections between said circumferential gear and the rotating elementof the motor, a brake shoe supported by the motor casing in operativerelation to the aforesaid brake drum, and

means exterior of the motor casing for actuating said brake shoe.

15. In a hoist of the class set forth, the combination of an electricmotor involving a casing, a drum surrounding the motor cas-' ing,anti-friction bearings throughwhich the drum is rotatably supported uponthe motor casing, an internal worm gear extending about the interior ofthe drum, a worm meshing with the worm gear, and drivin connectionsbetween the motor shaft an said Worm.

16. In a hoist of the class set forth, the combination of an electricmotor involving a casing, a drum surrounding the motor casabout itsequator, the axis of the motor beingthe drum is rotatably supported fromthe motor casing, an internal worm gear extending about the interior ofthe drum, a worm enclosed and su ported by the motor casing and meshinwith the internal worm gear, said worm aving a worm gear extendinginclinedto the plane of the internal worm gear thereby to dispose oneend of its shaft alongside said worm, and a worm mounted upon said endof the motor shaft for cooperation with the equatorial worm gear.

17. In a hoist of the class set .forth, the combination of an electricmotor involving a casin a drum surrounding the motor casing, all racesextendin about the motor casing and spaced apart axially of the drum,ball races fitted to the drum in opposed relation to the former ballraces, balls interposed between the opposed ball races, "an internalworm arextending about the interior of the rum, a worm enclosed andsupported by the motor casing and meshing with the internal worm gear,said worm having a worm gear extending about its equator, the axis ofthe motor being inclined to the plane of the internal worm gear therebyto dispose one end of its shaft alongside said worm, and a. worm mountedupon said end of the motor shaft for cooperation with the equatorialworm gear.

18. In a hoist of the class set forth, the

' combination of an electric motor involving a substantially sphericalcasin a drum surroundin the motor casing, t e motor casmg havmg annularshoulders in parallel planes spaced apart axially of the drum, ballraces mounted upon said shoulders, ball races carried by thedrum inopposed relation to the former ball races balls interposed between theopposed races, an internal worm gear extending about the interior of thedrum, a worm enclosed and sup orted by the motor casin in mesh with t einternal worm gear, said worm having a worm gear extending about itsequator, the axis of the motor being inclined to theplane of the nternalworm gear so as to dispose one of ts ends alongside said worm, and aworm mounted upon said end of the motor shaft andmeshing with theequatorial worm gear.

19. In a hoist of theclass set forth, the combination of, an electricmotor involving a casing, a drum surrounding the motor casmg, bearingsextending about the exterior of the motor casing andspaced apart axiallyof the drum and through which the drum is rotatably supported,aninternal worm gear extending about the interior of the drum, a wormwithin and supported by "the motor casing and meshing with the internalworm gear, one end of the motor shaft being disposed alongside the worm,driving connections between said end of the motor shaft and the worm,and a partition dividing the motor casing into a lubricant containingcompartment, enclosing said worm and the driving connection between itand the motor shaft, and a second compartment enclosing the electricalelements of the motor, said partition having an aperture through whichthe motor shaft extends.

20. In a hoist of the class set forth, the combination of an electricmotor involving a casing, a drum surrounding the motor casing, bearingsextending about the exterior of the motor casing and spaced apartaxially of the drum and through which the drum is rotatably supported,an internal worm gear extending about the interior of the drum, a wormwithin and supported by the motor casing and meshing with the internalworm gear, one end of the motor shaft being disposed alongside the worm,driving connections between said end of the motor shaft and the worm, apartition dividing the motor casing into a lubricant containingcompartment, enclosing said worm and the driving connections between itand the motor shaft, and a second com partment enclosing the electricalelements of the motor, said partition having an aperture through whichthe motor shaft extends, and av guard surrounding said aperture toprevent passage of lubricant from the first to the second of saidcompartments.

21. In a hoist of the class set forth, the combination of an electricmotor involving a casing, a drum surrounding the motor casing, bearingsextending about the exterior of the motor casing and spaced apartaxially of the drum and by which the drum is rotatably supported, aninternal worm gear surrounding the interior of the drum, a worm withinand supported by the motor casing and meshing with the internal wormgear one end of the motor shaft being disposed alongside the worm,driving connections between said end of the motor shaft and the worm, apartition dividing the motor casing into a lubricant containingcompartment, enclosing said worm and the driving connections between itand the motor shaft, and a second compartment enclosing 'the electricalelements of the motor, said partition havin an aperture through whichthe motor sha t extends, and a guard surrounding said aperture toprevent passage of lubricant from the first to the second of saidcompartments, a brake member carried by the rotating element of themotor, a second brake member carried by said partition for cooperationwith the first mentioned brake member, and means exterior of the casingfor actuating the second brake member.

combination with a supporting structure, a drum rotatablysupportedthereby, an electric motor carried by the structure, brakemechanism for controlling the motor, and a control element includingelectrical conductors and a switch through which current is supplied tothe motor, said element havcontrol element.

In testimony whereof, I hereunto aflix my signature.

THOMAS E. ADAMS.

